As one of methods of driving a liquid crystal display device, conventionally, there is a known method of “constructing one pixel by a plurality of (typically, two) sub-pixels and driving liquid crystal such that brightness of the plurality of sub-pixels varies one another) (hereinafter, referred to as a “pixel dividing method”). The pixel dividing method is employed to improve the view angle characteristic of a liquid crystal display device. It should be noted that, in the following, a region for forming one pixel (in the case of a liquid crystal display device performing color display by pixels of three colors of R, G, and B, a pixel of each of the colors) will be referred to as a “pixel portion”, and a region forming a sub-pixel will be referred to as a “sub-pixel portion”.
In a liquid crystal display device employing the pixel dividing method, the potential of a pixel electrode when a pixel capacitance is charged (hereinafter, referred to as “charging potential”) is set to be different in two sub-pixel portions. As configurations realizing it, a configuration that two gate bus lines GL1 and GL2 and one source bus line SL are assigned to one pixel portion 9 as illustrated in FIG. 17 (hereinafter, referred to as “2G-1D configuration”), a configuration that one gate bus line GL and two source bus lines SL1 and SL2 are assigned to one pixel portion 9 as illustrated in FIG. 18 (hereinafter, referred to as “1G-2D configuration”), and the like are known.
In a liquid crystal display device employing the 2G-1D configuration (refer to FIG. 17), by making the waveform of a scanning signal supplied to the gate bus line GL1 provided in correspondence with one of the sub pixel portions and that of a scanning signal supplied to the gate bus line GL2 provided in correspondence with the other sub pixel portion different from each other, the difference between the charging potentials is obtained between the two sub-pixel portions. In the configuration, the gate driver for driving the gate bus line is realized by providing, typically, one or a plurality of IC chips on both sides of a display unit (one end side and the other end side in a direction in which the gate bus line extends). The source driver for driving the source bus line is realized by providing, typically, one or a plurality of IC chips on one end side of the display unit (one end side in a direction in which the source bus line extends).
In a liquid crystal display device employing the 1G-2D configuration (refer to FIG. 18), by making the waveform of a video signal supplied to the source bus line SL1 provided in correspondence with one of the sub-pixel portions and that of a video signal supplied to the source bus line SL2 provided in correspondence with the other sub-pixel portion different from each other, the difference between the charging potentials is obtained between the two sub-pixel portions. In the configuration, the gate driver is typically realized by providing one or a plurality of IC chips on one end side of a display unit (one end side in a direction in which the gate bus line extends) or by being monolithically formed on a glass substrate on one end side of the display unit. The source driver is typically realized by providing one or a plurality of IC chips on both sides of the display unit (one end side and the other end side in a direction in which the source bus line extends).
It should be noted that configuration examples of a liquid crystal display device employing the pixel dividing method are disclosed in, for example, Japanese patent application laid-open No. 2004-62146, Japanese patent application laid-open No. 2008-145886, Japanese patent application laid-open No. 2007-86791, “55.3: Driving Method of Integrated Gate Driver for Large Area LCD-Tv” of SID 08 Digest”, and the like.